Hey, I think I read on a thread here that 3DHS recommend thin CA, thick CA and Welders adhesive glue for building and repairs. Can someone please tell me the following about Welders glue?

- basic glue type (i.e. is is polyurethane, expoxy, etc.)
- does it set on the hard side of flexible like 3M Scotch 6225N or the soft side of flexible like Uhu Por?
- is it safe to use with EPS (polystyrene) ?
- is it safe to use with Depron?

bleary, that's precisely why I asked . I don't yet know if 3DHS changed the main wing construction. I can see that the tail feathers are unchanged and therefore contain Depron sandwiched between layers of EPP. I am looking forward to seeing 3DHS' manual for the plane to see if they warn people about these issues. I expect they will since 3DHS manuals are very user-friendly.

Welders works great w/ EPP. Does NOT play well with Depron and most other foams.I've tried it on Dollar Tree Foam, and it melts it like some sick, flesh-eating virus! Not sure about EPS, but I'd be doubtful. With EPP, it's strong, flexible (makes great hinges), and easy to use.

Welders works great w/ EPP. Does NOT play well with Depron and most other foams.I've tried it on Dollar Tree Foam, and it melts it like some sick, flesh-eating virus! Not sure about EPS, but I'd be doubtful. With EPP, it's strong, flexible (makes great hinges), and easy to use.

Thanks EZglider. The Depron is in the tail, rudder, horizontal stabiliser and elevator only and is protected by a layer of EPP above and below, so Welders will be fine if it's used on the EPP alone. It's glues like thin CA that wick into the foam that can cause problems. I reckon that's why 3DHS are suggesting thick CA for parts of the build. I reckon the thin CA is for the hinges and for strengthening up the wood in areas like the motor mount.

If 3DHS' version uses the same construction as Skywing's then the main wing consists of an EPP skin with EPS underneath it, but the area where the hinges slot into is a bit of EPP with wood backing it, so you can use thin CA on the hinges SO LONG AS YOU ONLY USE A SMALL AMOUNT. IF YOU USE TOO MUCH THEN IT WILL EAT THE EPS BEHIND THE WOOD. ALSO, FOR THE CONTROL HORNS, ASSUMING THE SAME DESIGN AS A SKYWING KIT, THERE IS EPS UNDER THE EPP SKIN, SO USE MEDIUM OR THICK CA AND BE CAREFUL NOT TO LET IT RUN OFF THE WOOD AND SOAK THROUGH THE FOAM.

Last edited by groovejet; Dec 05, 2011 at 07:08 AM.
Reason: Clarified a few things

Actually, it's a technique that has been used on Hokusei planes for a very long time and it works very well. The EPP protects the Depron. You're far more likely to break the wood in the fuselage than the Depron in the tail feathers, but in any case, these planes are easy to repair, so long as you use a glue that is compatible with the various types of foam!!!

For the record, my favourite glue for fixing Depron and/or EPP damage is 3M Scotch 6225N http://www.bestvaluerc.com/shop/shopexd.asp?id=218. This glue dries white and forms a strong but slightly flexible bond. It does a fantastic job of repairing Depron and will stick very well to CF and EPP, among many other things BUT IT EATS EPS. I use this 3M glue for almost all of my Skywing repairs, but I also use polyurethane glue or PVA glue to repair the EPS inside the main wing.

Well I'm talking about polyurethane glue, I'm not sure if 3DHS have strengthened up the landing gear mount area. I'm confident that they have since anyone that flies these planes from a rough field will know that the Skywing mount is not particularly strong, but there's an easy fix for this which I actually borrowed from my 3DHS 47" Velox manual; coat the wood with polyurethane glue and it makes it as tough as nails.

Right, well I've said enough about potential areas of concern without knowing the full details of 3DHS' version of the Skywing planes, so I'll wait for more information on their particular version before giving any more advice on potential trouble spots.

Can it swing a 13x6.5?,this size plane likes lots of watts.It fly's ok on 300,much better on 400+.
A lighter motor may make CG iffy also,however as Groovejet says,dunno on this version,just going by my Skywing Extra 300.130g minimum on that one.